This removes the feature to be able to override log destinations from
the commandline.
This feature is removed because the --override-config feature from the
runtime already contains this functionality. It is a little more complex
to use, though this is a feature hardly used at all, so I rather go for
less code (less complexity) here than feature bloat.
Signed-off-by: Matthias Beyer <mail@beyermatthias.de>